Can someone tell me the difference between the 38mm and the 42mm Watch? Other then the size of the face. Someone said there was something the 42mm can do that the 38mm can’t. But they couldn’t remember what. TIA!

Thanks all! That's what I figured. She said there was something the 42mm can do that the 38 can't but I couldn't find any differences. One more question. Is it worth it to get the Apple Care on them? I ordered the watches from best buy and I have 60 days to get Apple Care + if I want it. Should I have gotten it?